Overview

Named after the strangler fig tree that grows around another tree and eventually replaces it, this pattern involves building a new system around the edges of the old one. A proxy or 'strangler facade' routes traffic to either the legacy system or the new service.

The Process

  1. Identify: Choose a small piece of functionality to migrate.
  2. Implement: Build the new service.
  3. Route: Update the facade to send traffic for that functionality to the new service.
  4. Repeat: Continue until the legacy system is no longer needed.

Benefits

  • Reduces the risk of a 'big bang' migration.
  • Allows for continuous delivery of value during the migration.

Related Terms